Ammut, or Ammit, is a mystical Egyptian beast awaiting in the Halls of Judgment before the afterlife. Should the heart of the judged soul be heavier than the Feather of Truth, Ammut devours the sinner.
Ammut can be found in the Monochrome Forest within the Expanse. It can teach Flynn the Megaton Press, War Cry, Nihil Claw and Energy Drain skills through its Demon Whisper.
Shin Megami Tensei IV Apocalypse
Ammut can teach Nanashi the Energy Drain, War Cry and Nihil Claw skills through its Demon Whisper. It benefits from learning Physical and support skills.
Devil Summoner: Soul Hackers
"A creature from Egyptian lore with the head of a crocodile, the front legs of a lion, and the hind legs of a hippo. When a person dies, he must be judged by Osiris. His heart is weighed on a scale, and if the heart is heavier than the feather of truth, their heart is given to Ammut to devour, denying the dead of eternal life."
—Devil Summoner: Soul Hackers 3DS compendium
Persona Q2: New Cinema Labyrinth
"A creature of Egyptian lore with the head of a crocodile, the front legs of a lion, and the hind legs of a hippo. When a man dies and is judged by Osiris, his heart is weighed on a scale to judge whether or not he speaks the truth."
—Persona Q2 explanation
Ammut is a physical sub-Persona of the Tower Arcana that can be summoned through special fusion once the Sinner's Canope is obtained through completing the "Shout of the Soul" special screening. In order to summon Ammut, the party will need Oni, Bicorn and Chimera.
Devil Survivor 2
"An Egyptian creature with the head of a crocodile, the front legs of a lion, and the hind legs of a hippopotamus. When humans die, their heart is weighed at the court of Osiris, deciding their fate. If the scales tip towards the heart, it is given to Ammut to eat. Those whose hearts are eaten cannot continue their journey toward immortality."
—Devil Survivor 2 compendium
Shin Megami Tensei: Liberation Dx2
"A creature of Egyptian lore with the head of a crocodile, the front legs of a lion, and the hind legs of a hippo. When a person dies, he must be judged by Osiris. His heart is weighed on a scale, and if the heart is heavier than the feather of truth, the heart is given to Ammut to devour, denying the dead of eternal life. His name means "the one who greedily devours"."